The production of organic hydroperoxides from aryl alkyl hydrocarbons in the presence of various transition metal salt complexes has been described in the literature. See, for example, U.S. Pat. No. 2,954,405 disclosing the production of organic hydroperoxides by autooxidation of hydrocarbons in the presence of molecular oxygen and metal phthalocyanines as catalysts. Similarly, U.S. Pat. No. 4,013,725 discloses a process for preparing hydroperoxides in a homogeneous system by autooxidizing secondary alkyl group-substituted methylbenzenes in the presence of water, a base, an oxygen containing gas, and a water-soluble chelate compound in which multidentate ligands are coordinated to at least one metal from the class of cobalt, nickel, manganese, copper, and iron.
In U.S. Pat. No. 5,025,101 and U.S. Pat. No. 5,183,945 tetranuclear manganese complexes, and their method of preparation, and their use as catalyst in the production of hydroperoxide are disclosed.
More recently, in copending U.S. Ser. No. 402,070 there is disclosed a new class of tetranuclear metal complexes having a mixed metal core. The present invention is predicated on the discovery that certain of those tetranuclear, mixed metal complexes are useful as catalysts in producing organic hydroperoxides.